Based on kernel version 4.15. Page generated on 2018-01-29 10:00 EST.
1 Virtual eXtensible Local Area Networking documentation 2 ====================================================== 3 4 The VXLAN protocol is a tunnelling protocol designed to solve the 5 problem of limited VLAN IDs (4096) in IEEE 802.1q. With VXLAN the 6 size of the identifier is expanded to 24 bits (16777216). 7 8 VXLAN is described by IETF RFC 7348, and has been implemented by a 9 number of vendors. The protocol runs over UDP using a single 10 destination port. This document describes the Linux kernel tunnel 11 device, there is also a separate implementation of VXLAN for 12 Openvswitch. 13 14 Unlike most tunnels, a VXLAN is a 1 to N network, not just point to 15 point. A VXLAN device can learn the IP address of the other endpoint 16 either dynamically in a manner similar to a learning bridge, or make 17 use of statically-configured forwarding entries. 18 19 The management of vxlan is done in a manner similar to its two closest 20 neighbors GRE and VLAN. Configuring VXLAN requires the version of 21 iproute2 that matches the kernel release where VXLAN was first merged 22 upstream. 23 24 1. Create vxlan device 25 # ip link add vxlan0 type vxlan id 42 group 184.108.40.206 dev eth1 dstport 4789 26 27 This creates a new device named vxlan0. The device uses the multicast 28 group 220.127.116.11 over eth1 to handle traffic for which there is no 29 entry in the forwarding table. The destination port number is set to 30 the IANA-assigned value of 4789. The Linux implementation of VXLAN 31 pre-dates the IANA's selection of a standard destination port number 32 and uses the Linux-selected value by default to maintain backwards 33 compatibility. 34 35 2. Delete vxlan device 36 # ip link delete vxlan0 37 38 3. Show vxlan info 39 # ip -d link show vxlan0 40 41 It is possible to create, destroy and display the vxlan 42 forwarding table using the new bridge command. 43 44 1. Create forwarding table entry 45 # bridge fdb add to 00:17:42:8a:b4:05 dst 18.104.22.168 dev vxlan0 46 47 2. Delete forwarding table entry 48 # bridge fdb delete 00:17:42:8a:b4:05 dev vxlan0 49 50 3. Show forwarding table 51 # bridge fdb show dev vxlan0